Interfacial Coupling Effect on Electron Transport in MoS2/SrTiO3 Heterostructure: An Ab-initio Study

Abstract

A variety of theoretical and experimental works have reported several potential applications of MoS2 monolayer based heterostructures (HSs) such as light emitting diodes, photodetectors and field effect transistors etc. In the present work, we have theoretically performed as a model case study, MoS2 monolayer deposited over insulating SrTiO3 (001) to study the band alignment at TiO2 termination. The interfacial characteristics are found to be highly dependent on the interface termination. With an insulating oxide material, a significant band gap (0.85eV) is found in MoS2/TiO2 interface heterostructure (HS). A unique electronic band profile with an indirect band gap (0.67eV) is observed in MoS2 monolayer when confined in a cubic environment of SrTiO3 (STO). Adsorption analysis showed the chemisorption of MoS2 on the surface of STO substrate with TiO2 termination which is justified by the charge density calculations that shows the existence of covalent bonding at the interface. The fabrication of HS of such materials paves the path for developing the unprecedented 2D materials with exciting properties such as semiconducting devices, thermoelectric and optoelectronic applications.

Efficient MoWO3/VO2/MoS2/Si UV Schottky photodetectors; MoS2 optimization and monoclinic VO2 surface modifications

“…Moreover, a redshift was observed for the trion peak and a slight blue shift when incorporating the VO 2 layer. The increase in PL intensity refers to an enhancement in light emission efficiency and increases the density of states of the carriers by modifying the band structure and consequently enhance the radiative recombination of carriers, similar results were observed in a compressively strained trilayer MoS 2 sheet 44,63,64 . This result shows that strong coupling between VO 2 and MoS 2 at 60 s Mo-O deposition time was observed at room temperature.…”

Recent Progress of Two-Dimensional Thermoelectric Materials

“…Recently, 2D TMDCs have collected a wide attention due to their special properties and are considered to be the next generation of high-performance thermoelectric materials [70,74,90,[175][176][177][178][179][180]. The measured Seebeck coefficient of single-layer MoS 2 can measure over 30 mV K −1 , providing an ideal candidate material for high-performance thermoelectric devices.…”

Single-Layer MoS2 Grown on Atomically Flat SrTiO3 Single Crystal for Enhanced Trionic Luminescence

“…In the extensively explored FSH systems, the two-dimensional materials (2DM) have emerged as an important participator owing to their remarkable properties including the superior conductivity, high chemical stability, conspicuously large surface area, as well as luminescing properties, etc . − The combination of 2DM with transition metal oxides (TMO) frequently constitutes more fascinating heterostructures seeing broad applications in various fields such as solar cells, photoconductors, photodetectors, and so on. − In such systems, a serious control of the interface structure can be more critical because the properties of the oxides can be sensitively dependent on their atomic structures and the ad-species, the latter may impose unexpected affections on the overall functionality of the heterostructure. As a representative of these FSH, the compositional system of MoS 2 and SrTiO 3 has attracted much interest considering the attractive properties of both materials. − Particularly, SrTiO 3 differs from many other oxides in its distinctive layered structure, high dielectric constant, quantum paraelectricity, etc . , and thus being expected with a special tuning effect over the MoS 2 properties. Recently, S. Sarkar et al discovered a quasiparticle in the MoS 2 /SrTiO 3 hybridization called “polaronic trion”, which is derived from the strong coupling of the soft phonon in SrTiO 3 and the negatively charged exciton in MoS 2 at the interface. , X. Yin and co-workers investigated the same system and discussed the importance of the spin–orbital charge–lattice coupling in tailoring the photo properties of the MoS 2 monolayer .…”